FudgeC2 - A Collaborative C2 Framework for Purple-Teaming

FudgeC2 – A Collaborative C2 Framework for Purple-Teaming

July 31, 2019 Comments Off

Fudge is a Python3/Flask web-based C2 framework and Powershell implant designed to facilitate purple teaming activities, post-campaign review and timelining.

Note: FudgeC2 is currently in alpha stage, and should be used with caution in non-test environments. Beta will be released at BlackHat Arsenal, the 8th of August 2019.

Fudges’ inception is based on 3 main areas:

Creating a suitable way for blue teamers to review the chronological activities a red team engagement, allowing them to assess if key alerts were missed.
Finding ways to incrementally increase detection rates, allowing defenders to identify the intrusion. This provides a gauge of skill & target areas for upskilling if the intrusion is not identified.
Providing a way for junior testers to experience red teaming without increasing risk to the campaign OpSec/client network.

Purple teaming was born out of the need for tighter integration between offensive and defensive teams. If the red team is successful in compromise, their ability to export the campaign timeline and logging can prove invaluable insight to the blue team. Allowing defenders to review network and host logs as they follow a campaign timeline, allows for blind spots to be identified and tooling adjusted and tuned.

Fudges’ implant also supports varying levels and types of obfuscation to allow for varying levels of noise to be made during the engagement to help a SoC benchmark their detection skills.

Lastly, Fudge is designed around team usage, which allows for a senior red teamer to allow another user to have read or read/write access to the campaign. These access controls allow a junior member to view the campaign and see the kind of commands, and techniques used in a post-exploitation environment.

FudgeC2 – A Collaborative C2 Framework for Purple-Teaming Features

Users within Fudge are divided into 2 groups, admins and standard users. Admins have all of the usual functionality, such as user and campaign creation, and are required to create a new campaigns.

Within campaign a users permissions can be configured to once of the following: None/Read/Read+Write. Without read permissions, a user will not be able to see the existence of a campaign, nor will they be able to read implant responses, or registered commands.

User with read permission will only be able to view the commands and their output, and the campaigns logging page. This role would typically be assigned to a junior tester, or an observer.

Users with write permissions will be able to create implant templates, and execute commands on all active implants.

Note: in further development this will become more granular, allow write permissions on specific implants.

User Creation

An admin can create a new user from within the Global Settings options. They will also have the option to configure a user with admin privileges.

What is a campaign?

A campaign is a method of organising a engagement against a client, which allows access control to be applied on a per user basis

Each campaign contains a unique name, implants, and logs while a user can be a member of multiple campaigns.

Implants

Implants are broken down into 3 areas

Implant Templates
Stagers
Active Implants

Implant Templates

An implant template is the what we will create to generate our stagers. The implant template wil contain the default configuration for an implant. Once the stager has been triggered and an active implant is running on the host this can be changed.

The list of required configurations are:

URL
Initial callback delay
Port
Beacon delay
Protocol:
- HTTP (default)
- HTTPS
- DNS
- Binary

Once a template has been created the stager options will be displayed in the Campaign Stagers page.

Stagers

The stagers are small scripts/macros etc which are responsible for downloaded and executing the full implant.

Once an implant has been generated the stagers page will provide a number of basic techniques which can be used to compromise the target. The stagers which are currently available are:

IEX method
Windows Words macro

Active Implants

Active implants are the result of successful stager executions. When a stager connects back to the Fudge C2 server a new active implant is generated, and delivered to the target host. Each stager execution & check-in creates a new active implant entry.

Example

As part of a campaign an user creates an implant template called “Moozle Implant” which is delivery to a HR department in via word macro. This then results in five successful execution of the macro stager; as a result the user will see five active implants.

These will be listed on the campaigns main implant page, with a six character unique blob. The unique implants will be listed something similar to below:

Moozle Implant_123459
Moozle Implant_729151
Moozle Implant_182943
Moozle Implant_613516
Moozle Implant_810021

Each of these implants can be individually interacted with, or using the “ALL” keyword to register a command against all active implants.

Implant communication

Implants will communicate back to the C2 server using whatever protocols the implant template was configured to use. If an implant is setup to use both HTTP and HTTPS, 2 listeners will be required to ensure that full commincation with the implant occurs.

Listeners are configured globally within Fudge from the Listeners page. Setting up and modifying the state of listeners requires admin rights, as changes to stagers may impact other on-going campaigns using the same Fudge server.

Currently the listeners page displays active listeners, but will allow admins to:

Create listeners for HTTP/S, DNS, or binary channels on customisable ports
Start created listeners
Stop active listeners
Assign common names to listeners

Implant configuration further info.

URL: An implant will be configured to call back to a given URL, or IP address.

Beacon time: [Default: 15 minutes] This is the time in between the implant calling back to the C2 server. Once an implant has been deployed it is possible to dynamically set this.

Protocols: The implant will be able to use of of the following protocols:

HTTP
DNS
Binary protocol

A user can enable and disable protocols depending on the environment they believe they are working in.

Setup

Installation

To quickly install & run FudgeC2 on a Linux host run the following:

git clone https://github.com/Ziconius/FudgeC2
cd FudgeC2/FudgeC2
sudo pip3 install -r requirements.txt
sudo python3 Controller.py

For those who wish to use FudgeC2 via Docker, a template Dockerfile exists within the repo as well.

Settings:

FudgeC2′ default server configurations can be found in the settings file:

<install dir>/FudgeC2/Storage/settings.py

These settings include FudgeC2 server application port, SSL configuration, and database name. For further details see the Server Configuration section.

N.b. Depending on your network design/RT architecture deployment, you will likely need to configure a number of proxy and routing adjustments.

For upcoming development notes and recent changes see the release.md file